In order to improve the ground it is fundamentally known to make material columns, such as for example gravel columns, in the ground. The production of such columns is carried out by way of example by using a vibrator arrangement with a spud vibrator which is mounted at the lower end of a pipe. The pipe can be a silo pipe for receiving material when the vibrator arrangement is formed as a so-called sluice vibrator for producing vibrating packing columns, or the pipe can be an extension pipe when the vibrator arrangement is formed as a “simple spud vibrator” for use with vibrating compression. For producing a column (vibrating packing column) the vibrator arrangement is hereby introduced with the silo pipe down to a desired depth into the ground whereby a column-like cavity is created which is initially filled up by the vibrator with the silo pipe. This cavity is then filled with the loose bulk material, such as for example with gravel. For this the vibrator arrangement is moved up and down step by step with the silo pipe. As the vibrator is moved upwards a cavity is formed underneath that of the vibrator arrangement which is filled up with the filler material from the silo pipe—which has an opening at its lower end. The material thus ejected is then compacted as the vibrator is moved down again. This process is repeated until a material column of the desired height is created.
When proceeding with vibration compression the particled ground is compacted by vibration without a column of foreign material being created. For this the spud vibrator is first lowered to the full compaction depth and then is lifted step by step, such as by way of example in steps of for example 0.5 to 1 m. After each lift the spud vibrator is stopped for a time in order to compact the surrounding ground before being raised further. The spud vibrator is brought in this way in stages up to the surface.
FIG. 1 shows a device with a vibrator arrangement 1 according to the prior art. The vibrator arrangement 1 with this device is held on a cable 6 which is guided over a roller head 3 which is fastened at an upper end of the vibrator arrangement 1. The cable 6 runs furthermore over a mast head roller 2 at the upper end of an excavator mast 8 of an excavator 4 and along the excavator mast 8 down to an excavator winch (not shown here). The useful length of the vibrator arrangement 1 which can penetrate into the ground amounts to z. This useful length determines the depth of the material column which can be produced in the ground by means of the vibrator arrangement 1.
With the known device a distance has to be kept from the mast roller 2, and shown in FIG. 1 by x. Furthermore, the roller head 3 which has a length y cannot penetrate into the ground. Thus of a total height t (=x+y+z) of the excavator 4 only a clearly smaller part, namely the part defined by the length z of the vibrator arrangement, can be used.
U.S. Pat. No. 3,309,877 describes a device with a vibrator arrangement which is held on a boom of an excavator. Two cables are guided over guide pulleys on the excavator up to the fastening points in the region of an upper end of the vibrator arrangement. During operation of the device a force can be applied to the vibrator by winding up the two cables whereby the vibrator can be inserted into the ground.
Further devices with vibrator arrangements are described in GB-L039645 or DE-A-578650.
Accordingly, it would be desirable to provide a device with a vibrator arrangement which has an overall height and with which a penetration depth of the vibrator arrangement into the ground corresponds to a greater part of the overall height than in the case of known devices of this kind.